Re: arith. expression crashes Kawa

[Jim White <jim at pagesmiths dot com>]

Jim White wrote:
> Sven.Hartrumpf@fernuni-hagen.de wrote:
>
> > With current CVS version of kawa, I get the following strange behavior:
> > ...
> ...
> I'ld wager that is a consequence of this change:
>
> cvs diff -D 2003-08-19 kawa/lib/numbers.scm
>
> 34,38c35,54
> < (define (quotient (x :: <integer>) (y :: <integer>)) :: <integer>
> <   (invoke-static <integer> 'quotient x y))
> <
> < (define (remainder (x :: <integer>) (y :: <integer>)) :: <integer>
> <   (invoke-static <integer> 'remainder x y))
> ---
>  > (define (quotient (x :: <real>) (y :: <real>)) :: <real>
>  >   (if (and (instance? x <integer>) (instance? y <integer>))
>  >       (invoke-static <integer> 'quotient x y)
>  >       (invoke (/ x y) 'toInt (static-field <number> 'TRUNCATE))))
>  >
> ...

I'm not sure if this is the right thing to do but changing the types for 
quotient from <real> to <number> gets it to work.  Changing just the 
return type to <integer> didn't work because that gets a 
ClassCastException when the result comes from the non-integer code.

Index: numbers.scm
===================================================================
RCS file: /cvs/kawa/kawa/kawa/lib/numbers.scm,v
retrieving revision 1.15
diff -u -r1.15 numbers.scm
--- numbers.scm 21 Aug 2003 07:03:00 -0000      1.15
+++ numbers.scm 18 Oct 2003 19:50:39 -0000
@@ -32,7 +32,7 @@
 (define (abs (x :: <number>)) :: <number>
   (invoke x 'abs))

-(define (quotient (x :: <real>) (y :: <real>)) :: <real>
+(define (quotient (x :: <number>) (y :: <number>)) :: <number>
   (if (and (instance? x <integer>) (instance? y <integer>))
       (invoke-static <integer> 'quotient x y)
       (invoke (/ x y) 'toInt (static-field <number> 'TRUNCATE))))

If this or anything similar is correct, then remainder needs the same 
treatment.

Jim
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